Ex situ seed banks and the IUCN Red List.

Extinct, or just extinct in the wild? Plants lost from in situ habitat, but represented in seed banks, are labelled extinct despite the potential for restoration. A change in the International Union for Conservation of Nature Red List definition of extinct in the wild is needed to improve the status and prospects of threatened plant species

Drought avoidance adaptive traits in seed germination and seedling growth of Citrullus amarus landraces

Abstract Citrullus lanatus cultivation is affected by drought stress. Citrullus species that grow wild and domesticated in arid areas, are considered potential useful donors of drought tolerance traits. Here, we evaluated the response of seed germination, seedling establishment and growth to different water availabilities in eleven landraces of C. amarus, from most of their cultivation range and in one C. lanatus commercial cultivar ('Sugar Baby'). 'Sugar Baby' germinated to lower water potential better than all C. amarus landraces, while seedling establishment was much higher in C. amarus than in C. lanatus. Finally, seedling growth of C. amarus landraces and the C. lanatus cultivar followed different patterns depending on water availability, showing enhanced biomass growth under wet conditions and no changes between dry and wet growing treatments, respectively. The different water use strategies in seed germination and seedling growth found in the two crops highlight drought avoidance strategies linked to the species growing environment in C. amarus, not present in the C. lanatus cultivar. The high seedling establishment, the plastic responses to water availabilities and the strong root system, indicate that genetic resources of C. amarus may have important applications in breeding programmes and in the selection of water-use efficient rootstock lines

Plant Regeneration Above the Species Elevational Leading Edge: Trade-Off Between Seedling Recruitment and Plant Production

Mountains and their biota are highly threatened by climate change. An important strategy that alpine plants use to escape this change consists in seed dispersal and the ability of seeds to germinate and establish in new sites at higher elevation. Little is known about the environmental factors that can affect the regeneration of plants above the elevational limit of growth. We present the first field evidence of recruitment success and plant performance in consequence of upward shift from the alpine to the nival life zone. Seeds of four alpine grassland species were sown at the current elevational limit of growth (site A) and 200 m upward, in a nival environment (site N) located in the Italian Alps. At site N part of the seeds were subjected to experimental manipulation of temperature (using an Open Top Chamber, OTC) or soil (using soil from site A). Recruitment success, soil surface temperature and water potential were monitored for five consecutive years. At the end of the experiment, vegetative growth and foliar traits were measured on individuals from all treatments. Mean annual soil surface temperature and length of the growing season at site A were ca. 2°C higher and ca. 44 days longer than at site N. Seedling emergence and seedling establishment generally were higher at N (with or without OTC) on local soil than at site A or at site N with soil originating from site A. Conversely, production was higher at site A and at site N with soil originating from site A. Recruitment success above the elevational leading edge was enhanced by coarser and nutrient-poor soil, which promoted seedling emergence and establishment but constrained plant growth. This trade-off between seedling recruitment and plant production underlines adaptive consequence and environmental filtering, both critical to forecast community assembly and responses of alpine species to climate warming

Global and Regional IUCN Red List Assessments: 11

In this contribution, the conservation status assessment of three vascular plants according to IUCN categories and criteria is presented. It includes the global assessment of Limonium parvifolium Tineo and Viscaria alpina (L.) G.Don, and the regional assessment of Rhazya stricta Decne. (Iraq)

Seed dormancy and seedling growth changes in response to scarification treatments and population origin in Kosteletzkya pentacarpos (Malvaceae)

Kosteletzkya pentacarpos is important for the restoration of coastal habitats in Asia and is vulnerable in Europe. Physical dormancy (PY) prevents ready seed germination and seedling production for restoration and conservation purposes. In this study, seed germination and seedling growth of K. pentacarpos were investigated in response to scarification treatments (manual scarification, percussion) and population origin (i.e., wild, cultivated ex situ and reintroduced). Manual scarification best promoted seed germination (98-100%), but resulted in damages to the cotyledons (on 64% of seedlings, on average) and lower seedling growth. Percussion did not significantly increase seed germination, but best promoted seedling growth. There was a significant reduction of PY in seeds produced by plants cultivated ex situ and/or reintroduced. Our results indicate that scarification treatments and ex situ cultivation may have important implications in translocation and other uses of K. pentacarpos

Ex situ collections and their potential for the restoration of extinct plants

The alarming current and predicted species extinction rates have galvanized conservationists in their efforts to avoid future biodiversity losses but for species extinct in the wild, few options exist. We posed the question, can these be restored, and if so, what role can ex situ plant collections (i.e. botanic gardens, germplasm banks and herbaria) play in the recovery of plant genetic diversity? We reviewed the relevant literature to assess the feasibility of recovering lost plant genetic diversity using ex situ material and the chances of survival of subsequent translocations. Thirteen attempts of recovering species extinct in the wild were found, most of which from material preserved in botanic gardens (12) and seed banks (2). A single case of a locally extirpated population was recovered from herbarium material. Eight (60%) of these cases were successful or partially successful translocations of the focal species or population, while the other five failed or was too early to judge. Our review exposes the many constraints of using ex situ source material for the restoration of plant genetic diversity to the wild, but also highlight the opportunities that modern collecting practices present for plant conservation. Limiting factors are the scarcity of available source material stored ex situ, low viability and reduced longevity of the material, low genetic variation, lack of evolution (especially for material stored in germplasm banks and herbaria) and socio‐economic constraints. However, our review suggests that all types of ex situ collections may effectively contribute to plant species conservation, if their use is informed by a thorough understanding of the aforementioned issues. For these reasons, we conclude that the recovery of plant species currently classed as extinct in the wild is not 100% successful and the possibility to achieve this should not be used as a justification for insufficient in situ conservation efforts

Conserving plant diversity in Europe: outcomes, criticisms and perspectives of the Habitats Directive application in Italy

Habitat Directive is the core strategy of nature conservation in Europe aiming at halting biodiversity loss. In this study the results of the third Italian assessment regarding the conservation status (CS) of plants listed in the Habitat Directive (Flora of community interest—FCI) was presented. Data was collected from several sources related to plant distribution, population data, habitats and pressures. Following the official European procedure, all parameters were evaluated and combined to give the CS of each taxon in each biogeographical region of presence. A comparison between the recent Italian IUCN and Reporting assessments was performed in order to evaluate the consistency between these two assessments. The official EU checklist comprises 113 Italian plant taxa, 107 of which were examined in this study. Our results showed a critical situation with only 34% of favourable CS, while 50% were unfavourable (40% inadequate plus 10% bad) and 16% unknown, in particular in the Mediterranean bioregion, where the unfavourable assessments reach the 65%. The results of the Report were consistent with those of the IUCN assessment, in which 41.9% of plants were threatened with extinction. This report highlighted some benefits and criticisms at national level, but it may have a wider significance. Although a general advance of knowledge, a great effort is needed to reach the Habitats Directive goals. Despite the limited resources, monitoring activities needs to be improved in order to close information gaps for several plants. A positive outcome was the development of a specific national project funded by the Italian Ministry of Environment, with the ambitious target to set future monitoring activities for FCI and optimize monitoring efforts